Endurance Bar:
This bar decreases as you spend time in the wilderness open to the elements; basically you’re slowly getting colder and colder, and its decrease can be temporarily quickened, for example when you wade through freezing water. Food and warmth have the ability to replenish this bar, and it’s important to keep an eye on the meter as if it depletes completely you’ll start losing life energy until endurance is restored. Warmth is found in the form of fire, and at ‘strategic’ points you’ll normally find some sort of fire; a wood-filled barrel or an enemy campfire.

Luring Enemies:
When in stealth mode and your sneaking up on enemies (most of the game) you can momentarily distract enemies by dropping a packet of cigarettes, etc. As you prepare for the kill. Also you will notice when facing multiple guards/enemies in a close area you can sneak up on one guard in stealth mode, kill him, move him out of the way, without other guards being aware of your actions.

Pilot Down: Behind Enemy Lines Official Website

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